CN110872709A - Cold extrusion processing technology of brake shoe roller shaft - Google Patents
Cold extrusion processing technology of brake shoe roller shaft Download PDFInfo
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- CN110872709A CN110872709A CN201810991960.7A CN201810991960A CN110872709A CN 110872709 A CN110872709 A CN 110872709A CN 201810991960 A CN201810991960 A CN 201810991960A CN 110872709 A CN110872709 A CN 110872709A
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- temperature
- brake shoe
- cold extrusion
- shoe roller
- oil
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C22/00—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C22/05—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions
- C23C22/06—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6
- C23C22/40—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates
- C23C22/42—Chemical surface treatment of metallic material by reaction of the surface with a reactive liquid, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using aqueous solutions using aqueous acidic solutions with pH less than 6 containing molybdates, tungstates or vanadates containing also phosphates
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D3/00—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts
- B21D3/10—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts between rams and anvils or abutments
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
- B24C1/00—Methods for use of abrasive blasting for producing particular effects; Use of auxiliary equipment in connection with such methods
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/28—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for plain shafts
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention discloses a cold extrusion processing technology of a brake shoe roller shaft, belonging to the technical field of machine part processing and comprising the following steps: the method comprises the following steps of taking oil steel as a raw material, blanking according to a specified size, and then sequentially carrying out annealing, flat-heading, shot blasting, phosphorization and saponification treatment, cold extrusion and shaping, machining, quenching, tempering, shot blasting, cleaning, grinding machine machining and waste recovery to obtain the finished brake shoe roller shaft. The brake shoe roller shaft obtained by the process has the advantages of high precision, small difference among individuals, good strength performance and long service life.
Description
Technical Field
The invention relates to the technical field of machine part machining, in particular to a cold extrusion machining process of a brake shoe roller shaft.
Background
The vehicle brake is an important part of the vehicle and is the key for ensuring the driving safety. Currently used vehicle brakes include drum brakes and disc brakes. The drum brake widely used in domestic trailers, semitrailers and trucks at present consists of a brake bottom plate, brake shoes, friction linings, brake shoe supporting pins, a cam shaft, a return spring, an adjusting arm, a tension spring, a roller shaft, rollers and other parts. When the brake is stepped, the cam curved surface of the cam shaft pushes the roller to open the brake shoe, and a friction lining on the brake shoe is contacted with the inner cylindrical surface of the rotating brake drum to generate a friction resistance distance to implement braking.
In the prior art, the roller shaft is complex in structure, generally made of 45# oil steel through hot forging and machining, the forging process is complex, the production efficiency is low, particularly, each surface of a part needs to be machined after forging, the machining amount is large, and the production cost of the product is high. Some factory tests adopt an extrusion process for processing, but due to the factors of unreasonable process design, overlarge deformation and the like, a large number of cracks exist on the surface of a product, and a qualified product cannot be obtained.
Disclosure of Invention
The invention aims to provide a cold extrusion processing technology of a brake shoe roller shaft aiming at the defects of the prior art, most surfaces of products are directly formed after being extruded, so that the surface processing amount is small, the processing cost is reduced, and the production efficiency is improved.
The technical scheme adopted by the invention is as follows:
a cold extrusion processing technology of a brake shoe roller shaft comprises the following steps: the method comprises the following steps of taking oil steel as a raw material, blanking according to a specified size, and then sequentially carrying out annealing, flat-heading, shot blasting, phosphorization and saponification treatment, cold extrusion and shaping, machining, quenching, tempering, shot blasting, cleaning and grinding machine machining to obtain the finished brake shoe roller shaft.
The annealing is carried out in an industrial quenching resistance furnace, the annealing temperature is 750-800 ℃, and the annealing time is 6-7 h.
The shot blasting refers to performing surface shot blasting treatment by using cast steel shots, and the shot blasting time is 5-6 min.
The phosphorization and saponification treatment comprises phosphorization treatment and saponification treatment, wherein the phosphorization treatment comprises the following steps:
a 1: rinsing the oil steel material subjected to surface shot blasting twice with clear water to remove dust on the surface of the oil steel;
a 2: removing oil stains on the surface of the oil steel material after dust removal by using deoiling agent at the temperature of 80-90 ℃;
a 3: rinsing the oil steel material subjected to oil stain removal twice by using hot water at the temperature of 70-80 ℃ to remove the residual oil remover on the surface;
a 4: and (b) immersing the oil steel material treated in the step a3 into a phosphating solution for phosphating, wherein the phosphating solution comprises the following components in percentage by weight: 15-20% of zinc oxide, 20-25% of zinc dihydrogen phosphate, 15-25% of nitric acid, 6-10% of citric acid, 1-3% of nickel sulfate, 1-3% of sodium molybdate and the balance of water, wherein the phosphating conditions are as follows: the Total Acidity (TA) is 40-60Pt, the Free Acidity (FA) is 7-10Pt, the acid ratio is TA/FA6-8, the accelerator (AC value) is 1-3Pt, the phosphating temperature is 70-80 ℃, and the phosphating time is 10-15 min;
a 5: filtering the phosphated oil steel material with clean water at normal temperature for 20-40 s, and removing residual phosphating solution on the surface;
a 6: and soaking the oil steel material filtered by clear water in hot water at the temperature of 70-80 ℃ for 40-60 s to improve the temperature of the machined part.
a 7: soaking the workpiece heated by hot water into saponification liquid for saponification, wherein the saponification liquid is a water-soluble substance of sodium stearate, the mass ratio of the sodium stearate to water is 1: 8, the solution temperature is 70-80 ℃, and the soaking time is 40-60 s.
And performing cold extrusion and shaping on a high-speed cold extrusion forming machine provided with a shaping die, immediately putting the oil steel material subjected to phosphorization and saponification treatment into a female die of the shaping die, pressing a core rod of the shaping die into the female die, and positively extruding the oil steel material by a punch with the impact force of 300 tons through a hydraulic machine to form a brake shoe roller shaft blank.
The quenching is carried out in a multi-purpose furnace, the furnace is placed in a furnace with the furnace temperature less than or equal to 300 ℃, the temperature is increased to 800-850 ℃, the temperature is maintained for 0.5h, and the temperature is quickly increased to 900-9500 ℃ for short-time heat preservation. The temperature and time of this step are important to harden the material, increase strength, and increase service life.
The tempering is carried out in an industrial tempering furnace, the tempering temperature is 200 ℃, and the tempering time is 1.5 hours. The step is a post-treatment of quenching, and after the step, the fatigue resistance, the toughness and the wear resistance of the material are greatly improved.
Compared with the prior art, the invention has the following remarkable advantages and beneficial effects:
(1) according to the invention, the flat head is firstly carried out after the oil steel is blanked, the indexes of the flat head process are that the quality of each oil steel material is equal, namely, the quality consistency among individuals is strictly ensured at the previous stage, the oil steel materials with the same quality are directly shaped, and the step of influencing the quality of the materials such as boring and the like is not carried out in the middle, so that the consistency of the shape and the size of the sleeve blank obtained after the shaping of the die is very high, the deviation among samples is small, the precision is high, the internal quality of the sleeve blank is uniformly distributed, the density consistency among the samples is high, and the difference among batches is small;
(2) after annealing treatment, shot blasting is firstly carried out to remove an oxide layer on the surface of the oil steel material, then phosphorization and saponification are carried out, so that the phosphorization effect can be greatly improved, and the formed phosphate layer is uniform in thickness, smooth in surface, compact in combination and not easy to fall off;
(3) the phosphating solution and the dipping treatment method thereof have the characteristics of low use temperature (70-80 ℃), short phosphating time (10-15 min) and less sediment, and after phosphating, a zinc phosphate film with the film weight of 8-10g/m2 is generated on the surface of a metal, the film is compact and uniform and has no ash hanging, the film obtained by the phosphating solution has good stability to a lubricant, and the film is most suitable for being used as a lubricating bottom film during cold heading;
(4) the quenching and tempering play a key role in the invention, and the strength, the toughness and the tensile strength of the material are greatly improved and the service life is prolonged through the synergistic effect between the quenching and tempering.
Detailed Description
The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without any inventive step, are within the scope of the present invention.
Example 1
The method comprises the following steps of taking oil steel as a raw material, and carrying out annealing, flat heading, shot blasting, phosphorization and saponification treatment, cold extrusion and shaping, machining, quenching, tempering, shot blasting, cleaning and grinding machine machining in sequence after the oil steel is fed by a sawing machine according to specification and size to obtain the finished brake shoe roller shaft.
The annealing is carried out in an industrial quenching resistance furnace, the annealing temperature is 750-800 ℃, and the annealing time is 6-7 h. The annealing temperature is slightly lower than that of the prior art, and the treatment process is tested to meet the use requirement mainly for cost reduction.
The tack is carried out according to conventional techniques, but it is noted that the standard of performance of tack is a strict guarantee of quality consistency between individuals.
The shot blasting refers to performing surface shot blasting treatment by using cast steel shots, and the shot blasting time is 5-6 min. The method effectively removes an oxide layer generated on the surface of the oil steel pipe material in the annealing step, so that the subsequent phosphating treatment effect is good.
The phosphorization and saponification treatment comprises phosphorization treatment and saponification treatment, wherein the phosphorization treatment comprises the following steps:
a 1: rinsing the oil steel pipe material subjected to surface shot blasting twice with clear water to remove dust on the surface of the oil steel pipe;
a 2: removing oil stains on the surface of the oil steel pipe material after dust removal by using deoiling agent at the temperature of 80-90 ℃;
a 3: rinsing the oil steel pipe material subjected to oil stain removal twice by using hot water at the temperature of 70-80 ℃ to remove the residual oil removal agent on the surface;
a 4: and (b) immersing the oil steel pipe material treated in the step a3 into a phosphating solution for phosphating, wherein the phosphating solution comprises the following components in percentage by weight: 15-20% of zinc oxide, 20-25% of zinc dihydrogen phosphate, 15-25% of nitric acid, 6-10% of citric acid, 1-3% of nickel sulfate, 1-3% of sodium molybdate and the balance of water, wherein the phosphating conditions are as follows: the Total Acidity (TA) is 40-60Pt, the Free Acidity (FA) is 7-10Pt, the acid ratio is TA/FA6-8, the accelerator (AC value) is 1-3Pt, the phosphating temperature is 70-80 ℃, and the phosphating time is 10-15 min;
a 5: filtering the phosphated oil steel pipe material with normal-temperature clear water for 20-40 s, and removing residual phosphating solution on the surface;
a 6: and soaking the oil steel pipe material filtered by clean water in hot water of 70-80 ℃ for 40-60 s to improve the temperature of the machined part.
a 7: soaking the workpiece heated by hot water into saponification liquid for saponification, wherein the saponification liquid is a water-soluble substance of sodium stearate, the mass ratio of the sodium stearate to water is 1: 8, the solution temperature is 70-80 ℃, and the soaking time is 40-60 s.
And performing cold extrusion and shaping on a high-speed cold extrusion forming machine provided with a shaping die, immediately putting the oil steel pipe material subjected to phosphorization and saponification treatment into a female die of the shaping die, pressing a core rod of the shaping die into the female die, and positively extruding the oil steel pipe material by a punch with the impact force of 300 tons through a hydraulic machine to form a brake shoe roller shaft blank. The purpose of this step is to make the outer dimensions of the blank uniform.
The machining refers to finish machining of the inner surface and the outer surface of the isolator spline sleeve blank and end face chamfering machining (machining of product size) by using a numerical control lathe, and comprises chamfering, turning, grinding and the like, and the machining method adopts a common machining method.
The quenching is carried out in a multi-purpose furnace, the furnace is placed in a furnace with the furnace temperature less than or equal to 300 ℃, the temperature is increased to 800-850 ℃, the temperature is kept for 0.5h, and then the temperature is quickly increased to 900-9500 ℃ for short-time heat preservation.
The tempering is carried out in an industrial tempering furnace, the tempering temperature is 200 ℃, and the tempering time is 1.5 hours.
The cleaning is carried out by using an aqueous cleaning solution.
The grinding machine processing refers to the processing of the surface and the inner hole with precision and smoothness, and adopts the conventional process.
The use frequency of the brake shoe roller shaft obtained by the treatment process can reach 30000-50000 times, and the working environment requirements of high working load and high frequency action of an automobile engine are completely met.
Claims (7)
1. A cold extrusion processing technology of a brake shoe roller shaft is characterized by comprising the following steps: the method comprises the following steps of taking oil steel as a raw material, blanking according to a specified size, and then sequentially carrying out annealing, flat-heading, shot blasting, phosphorization and saponification treatment, cold extrusion and shaping, machining, quenching, tempering, shot blasting, cleaning and grinding machine machining to obtain the finished brake shoe roller shaft.
2. The cold extrusion process for brake shoe roller shafts according to claim 1, wherein: the annealing is carried out in an industrial quenching resistance furnace, the annealing temperature is 750-800 ℃, and the annealing time is 6-7 h.
3. The cold extrusion process for brake shoe roller shafts according to claim 1, wherein: the shot blasting refers to performing surface shot blasting treatment by using cast steel shots, and the shot blasting time is 5-6 min.
4. The cold extrusion process for brake shoe roller shafts according to claim 1, wherein: the phosphorization and saponification treatment comprises phosphorization treatment and saponification treatment, wherein the phosphorization treatment comprises the following steps: a 1: rinsing the oil steel material subjected to surface shot blasting twice with clear water to remove dust on the surface of the oil steel; a 2: removing oil stains on the surface of the oil steel material after dust removal by using deoiling agent at the temperature of 80-90 ℃; a 3: rinsing the oil steel material subjected to oil stain removal twice by using hot water at the temperature of 70-80 ℃ to remove the residual oil remover on the surface; a 4: and (b) immersing the oil steel material treated in the step a3 into a phosphating solution for phosphating, wherein the phosphating solution comprises the following components in percentage by weight: 15-20% of zinc oxide, 20-25% of zinc dihydrogen phosphate, 15-25% of nitric acid, 6-10% of citric acid, 1-3% of nickel sulfate, 1-3% of sodium molybdate and the balance of water, wherein the phosphating conditions are as follows: the total acidity is 40-60Pt, the free acidity is 7-10Pt, the acid ratio is TA/FA6-8, the accelerator is 1-3Pt, the phosphating temperature is 70-80 ℃, and the phosphating time is 10-15 min; a 5: filtering the phosphated oil steel material with clean water at normal temperature for 20-40 s, and removing residual phosphating solution on the surface; a 6: and soaking the oil steel material filtered by clear water in hot water at the temperature of 70-80 ℃ for 40-60 s to improve the temperature of the machined part. a 7: soaking the workpiece heated by hot water into saponification liquid for saponification, wherein the saponification liquid is a water-soluble substance of sodium stearate, the mass ratio of the sodium stearate to water is 1: 8, the solution temperature is 70-80 ℃, and the soaking time is 40-60 s.
5. The cold extrusion process for brake shoe roller shafts according to claim 1, wherein: and performing cold extrusion and shaping on a high-speed cold extrusion forming machine provided with a shaping die, immediately putting the oil steel material subjected to phosphorization and saponification treatment into a female die of the shaping die, pressing a core rod of the shaping die into the female die, and positively extruding the oil steel material by a punch with the impact force of 300 tons through a hydraulic machine to form a brake shoe roller shaft blank.
6. The cold extrusion process for brake shoe roller shafts according to claim 1, wherein: the quenching is carried out in a multi-purpose furnace, the furnace is placed in a furnace with the furnace temperature less than or equal to 300 ℃, the temperature is increased to 800-850 ℃, the temperature is kept for 0.5h, and then the temperature is quickly increased to 900-9500 ℃ for short-time heat preservation.
7. The cold extrusion process for brake shoe roller shafts according to claim 1, wherein: the tempering is carried out in an industrial tempering furnace, the tempering temperature is 200 ℃, and the tempering time is 1.5 hours.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810991960.7A CN110872709A (en) | 2018-08-29 | 2018-08-29 | Cold extrusion processing technology of brake shoe roller shaft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810991960.7A CN110872709A (en) | 2018-08-29 | 2018-08-29 | Cold extrusion processing technology of brake shoe roller shaft |
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| Publication Number | Publication Date |
|---|---|
| CN110872709A true CN110872709A (en) | 2020-03-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810991960.7A Withdrawn CN110872709A (en) | 2018-08-29 | 2018-08-29 | Cold extrusion processing technology of brake shoe roller shaft |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115301886A (en) * | 2022-10-09 | 2022-11-08 | 靖江市永恒汽车科技有限公司 | Cold extrusion processing forming equipment for brake shoe roller shaft |
-
2018
- 2018-08-29 CN CN201810991960.7A patent/CN110872709A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115301886A (en) * | 2022-10-09 | 2022-11-08 | 靖江市永恒汽车科技有限公司 | Cold extrusion processing forming equipment for brake shoe roller shaft |
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Application publication date: 20200310 |
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| WW01 | Invention patent application withdrawn after publication |